The St. Louis Rams convinced a panel of arbitrators that the Edward Jones Dome would need a major overhaul to transform into a top stadium, setting the stage for the next round of talks over St. Louis' football future: a new stadium.

The three arbitrators on Friday ruled that the Rams' proposal for a dramatic renovation of the Dome — estimated to cost at least $700 million — was the only way to make the building a "first tier" football facility.

The St. Louis Convention and Visitors Commission, which runs the Dome, now has 30 days to decide if it will try to enact the Rams' plan. But one of its lead attorneys, Greg Smith, said Friday that was "unlikely."

If the CVC rejects the plan, as expected, the Rams' lease at the Dome will go to a year-to-year basis starting in March 2015, freeing the team to potentially leave St. Louis for Los Angeles or another city.

But talks between local leaders and the Rams are expected to shift toward the idea of building a new stadium, on a new site.

Jeff Rainford, chief of staff for St. Louis Mayor Francis Slay, said Friday's ruling was only one step "in the journey through the whole process."

"We now have clarity," Rainford said. "The Rams will hopefully let everyone know what they really want, and we'll see what we can do to help."

The three arbitrators, from the American Arbitration Association, were: retired Colorado judge Federico C. Alvarez, from Denver; former Iowa judge David Blair, from Sioux City; and labor attorney Sinclair Kossoff, from Chicago.

They were brought in to decide whether a proposal from the CVC, or one from the Rams, would propel the Dome into "first tier" status, defined as the top 25 percent of NFL stadiums, in several categories. The Rams' lease at the Dome runs through 2025, but the team is allowed to break the lease and go on a year-to-year basis if the building is not a "first tier" facility by 2015.